On the Water with Harbor Seals
Book your charter now for sunset cruising with harbor seals on the Hood Canal! Wildlife lovers need barely scan the waters to see “the puppy of the water:” seals. As the most common marine mammal on the Pacific Coast, the Harbor seal (Phoca vitulina) delights viewers from the Southern tip of California to the frigid waters of Alaska. These well-camouflaged speckled greyish-blue seals are often seen hauled out on shore or cruising through the water curiously peeping back at the human visitors to their world!
When seals come to shore, it’s called “hauling out.” In the Hood Canal, observations have revealed that these non-migratory seals appear to return to preferred haul-out sites regularly to rest and molt, birth and nurse pups, avoid predators, regulate their temperature, and engage in social interaction. Favorite slough-edge sites like the Duckabush and Dosewallips estuaries appear to provide the seals with safe, level resting spots and easy access to deeper waters during high tides.
Pups & Lifespan
The gender and age of seals greatly influences their behavior during haul-outs. For example, while a newborn seal pup can swim from birth, babies often remain on shore while mothers hunt for sustenance. While pups only have about a 50% chance of making it to adulthood, they are particularly vulnerable while on shore. People and their pets should give these pups plenty of distance, as the mother may not return if she senses a threat. Seals on the Hood Canal typically give birth to a single pup a year from July through October after a 10-month gestation. Pups nurse for 4-6 weeks on a milk with 42% fat to quickly build up their blubber layer. In their first years, pups continue to develop towards sexual maturity at 3-5 years with a lifespan up to 35 years.
Diet & Hunting Behaviors
As opportunistic foragers, seal diet reveals seasonal changes in abundance of prey. When not on shore, these seals are often hunting the depths of the Hood Canal for more than 20 minutes. They can eat up to 10% of their body weight daily! Given their elevated position on the food chain and relatively long lifespans, the diet of seals can also be an indicator of pollution levels in the Puget Sound. Observations of seal scat reveal that they largely consume Pacific Hake (whiting) and herring year-round with fall salmon being replaced by spring anchovies.
Sleeping & Thermoregulation
Since seals can also sleep just below the surface of the water, surfacing every 5-10 minutes to breathe without waking up, it can be very difficult to estimate population numbers! Sometimes, they will sleep in a position known as “bottling,” where their body is positioned vertically in the water with just their heads above the surface. While a seal maintains its core temperature at about 100 degrees Fahrenheit, their body temperature steadily drops to only about 2 degrees warmer than their environment at their skin.
Threats & History
Harbor seal populations in the Puget Sound were dramatically reduced from 1947-1960 by a state-financed population control program in an effort to curb their impact on salmon numbers. After nearly 20,000 seals were killed, with no positive impact on salmon populations, the program ended. By 1972, Salish Sea seals were protected by the Marine Mammal Protection Act (MMPA), and it’s estimated that they have reached their Optimum Sustainable Population with a Hood Canal population of around 1500 individuals and Salish Sea population of around 50,000. As a protected species under the MMPA, seals must be given space without being harassed, harmed, or pursued. The MMPA dictates that visitors must give seals a 50-yard distance.
While people often think of predators such as killer whales, sea lions, eagles, dogs, coyotes, and bears as reducing seal populations, they are much more impacted by persistent organic pollutants (POPs), vessel strikes, and incidental fishery catches/gear entanglement.
How to Get on the Water
Eager to go sunset cruising with harbor seals on the Hood Canal? Give us a call or text at 360-300-7810 to schedule your custom trip!